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The purpose of this study is to verify the moderating effects of consultant's problem-solving ability on the effect of client advance readiness on consulting satisfaction. The survey subjects were the employees who participated in internal consulting project with external professional consultants and questionnaire method was used. The survey was conducted through e-mail and direct questionnaire responses for about 2 months from February 2017. 500 questionnaire were distributed, and 276 responses were finally used for the analysis. Statistical program SPSS 23.0 was used to analyze the validity and reliability, followed by the moderating regression analysis to verify the hypothesis. The result of this study showed that client's advance readiness for consulting had a significant effect on consulting satisfaction. In addition, consultant's problem-solving ability was confirmed to have a significant moderating effect on the influence of client's advance readiness on consulting satisfaction. This study provides implications for the consultant's role as well as the importance of client's advance readiness for consulting before proceeding the consulting project to improve consulting satisfaction of the company using consulting service. Future studies are required to find out various methods to improve client's advance readiness before consulting project and consultant's problem-solving ability. [ABSTRACT FROM AUTHOR]

Background and purpose: Differentiation between parkinsonian type multiple system atrophy (MSA-P) and Parkinson’s disease (PD) is important but often difficult. We investigated the diagnostic value of brain magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) in differentiating MSA-P from PD. Methods: Twenty-four patients with MSA-P (16 probable and 8 possible) and eight patients with PD were included in this study. Results: For analysis using the putaminal findings, the sensitivities were 58.3% by visual analysis of brain MRI, 95.8% by visual analysis of 18F-FDG PET, and 79.2% by statistical parametric mapping (SPM) analysis of 18F-FDG PET in differentiating MSA-P from PD; the specificity was 100% for each analysis. Using the putaminal findings, visual analysis of 18F-FDG PET had a higher sensitivity compared with brain MRI ( P = 0.004) and SPM analysis of 18F-FDG PET revealed a tendency towards higher sensitivity compared with brain MRI ( P = 0.063). For analysis using both putaminal and infratentorial findings, the sensitivities were 79.2% by visual analysis of brain MRI, 95.8% by visual analysis of 18F-FDG PET, 95.8% by SPM analysis of 18F-FDG PET in differentiating MSA-P from PD; the specificity was 100% for each analysis. Conclusion: Both brain MRI and 18F-FDG PET showed diagnostic usefulness in differentiating MSA-P from PD, with 18F-FDG PET being more sensitive than brain MRI. [ABSTRACT FROM AUTHOR]

Studies of the grown-in defects in multi-epilayer GaAs (with/without a buffer layer) grown by metalorganic chemical vapor deposition under different [AsH3]/[TMGa] ratios, growth temperatures, and growth rates have been made in this letter by the deep level transient spectroscopy method. For samples without a buffer layer, two electron traps with activation energies of Ec-0.83 eV (EL2a) and Ec-0.74 eV are observed, whereas for samples with 6-μm-thick buffer layers, only EL2a level is found. The concentration of the deep level traps is found closely related to the [AsH3]/[TMGa] ratio, the growth temperature, and the growth rate (mainly at lower growth rate). The results show that, for samples without a buffer layer, the background dopant density profile is closely related to the deep level trap density profile in the epilayers, whereas for samples with a buffer layer, the profile of background dopant density is less influenced by the presence of the deep level trap. [ABSTRACT FROM AUTHOR]

Background: Accurate diagnosis of tumefactive demyelinating lesions is clinically important to avoid unnecessary invasive biopsy or inappropriate treatment., Purpose: We aimed to evaluate conventional and advanced MR imaging findings of tumefactive demyelinating lesions and determine the diagnostic performance of MR imaging for differentiating tumefactive demyelinating lesions from primary brain tumor., Data Sources: A systematic search of Ovid MEDLINE and EMBASE up to December 6, 2017, was conducted., Study Selection: Original articles describing MR imaging findings in patients with tumefactive demyelinating lesions were selected., Data Analysis: The pooled incidences of conventional MR imaging findings of tumefactive demyelinating lesions were obtained with the DerSimonian and Liard random-effects model. The pooled sensitivity and specificity of MR imaging for differentiating tumefactive demyelinating lesions from primary brain tumor were obtained using the bivariate random-effects model., Data Synthesis: Nineteen eligible studies with 476 patients with tumefactive demyelinating lesions were included. The pooled incidence of open ring or incomplete rim enhancement was 35% (95% CI, 24%-47%), which was significantly higher than the incidence of closed ring or complete rim enhancement (18% [95% CI, 11%-29%]; P = .0281). The pooled incidences of T2 hypointense rim, absent or mild mass effect, and absent or mild perilesional edema were 48%, 67%, and 57%, respectively. On advanced MR imaging, tumefactive demyelinating lesions showed a high apparent diffusion coefficient, peripheral restricted diffusion, and low cerebral blood volume. The pooled sensitivity and specificity of MR imaging for differentiating tumefactive demyelinating lesions from primary brain tumor were 89% (95% CI, 82%-93%) and 94% (95% CI, 89%-97%), respectively., Limitations: Seventeen of 19 studies were retrospective studies., Conclusions: Conventional MR imaging findings may help differentiate tumefactive demyelinating lesions from primary brain tumor, though further study is needed to determine the added value of advanced MR imaging., (© 2018 by American Journal of Neuroradiology.)

Background: O6-methylguanine methyltransferase ( MGMT ) promoter methylation status has been reported as a prognostic biomarker in clinical trials., Purpose: Our aim was to systematically evaluate imaging features of MGMT promoter methylated glioblastoma and to determine the diagnostic performance of MR imaging for prediction of MGMT promoter methylation in patients with newly diagnosed glioblastoma., Data Sources: A computerized search of Ovid MEDLINE and EMBASE up to February 27, 2018, was conducted., Study Selection: We selected studies evaluating imaging features of MGMT promoter methylated glioblastoma and the diagnostic performance of MR imaging for prediction of MGMT promoter methylation., Data Analysis: Pooled estimates of sensitivity and specificity were calculated using a hierarchic logistic regression model. Meta-regression and sensitivity analysis were performed., Data Synthesis: Twenty-two articles including 2199 patients were included. MGMT promoter methylated glioblastoma is likely to show less edema, high ADC, and low perfusion. Ten articles including 753 patients were included in the meta-analysis. The summary sensitivity was 79% (95% CI, 72%-85%), and the summary specificity was 78% (95% CI, 71%-84%). In the meta-regression, MGMT promoter methylation and mean age were associated with heterogeneity. Sensitivity analysis excluding 1 study resolved the heterogeneity., Limitations: Included studies used a variety of different MR imaging techniques to predict MGMT promoter methylation., Conclusions: MGMT promotor methylated glioblastoma is likely to show less aggressive imaging features than MGMT promotor unmethylated glioblastoma. Despite the variety of different MR imaging techniques used, MR imaging in patients with newly diagnosed glioblastoma was shown to have the potential to predict MGMT promoter methylation noninvasively., (© 2018 by American Journal of Neuroradiology.)

Background and Purpose: High-resolution MR imaging has recently been introduced as a promising diagnostic modality in intracranial artery disease. Our aim was to compare high-resolution MR imaging with digital subtraction angiography for the characterization and diagnosis of various intracranial artery diseases., Materials and Methods: Thirty-seven patients who had undergone both high-resolution MR imaging and DSA for intracranial artery disease were enrolled in our study (August 2011 to April 2014). The time interval between the high-resolution MR imaging and DSA was within 1 month. The degree of stenosis and the minimal luminal diameter were independently measured by 2 observers in both DSA and high-resolution MR imaging, and the results were compared. Two observers independently diagnosed intracranial artery diseases on DSA and high-resolution MR imaging. The time interval between the diagnoses on DSA and high-resolution MR imaging was 2 weeks. Interobserver diagnostic agreement for each technique and intermodality diagnostic agreement for each observer were acquired., Results: High-resolution MR imaging showed moderate-to-excellent agreement (interclass correlation coefficient = 0.892-0.949; κ = 0.548-0.614) and significant correlations (R = 0.766-892) with DSA on the degree of stenosis and minimal luminal diameter. The interobserver diagnostic agreement was good for DSA (κ = 0.643) and excellent for high-resolution MR imaging (κ = 0.818). The intermodality diagnostic agreement was good (κ = 0.704) for observer 1 and moderate (κ = 0.579) for observer 2, respectively., Conclusions: High-resolution MR imaging may be an imaging method comparable with DSA for the characterization and diagnosis of various intracranial artery diseases., (© 2016 by American Journal of Neuroradiology.)

Background and Purpose: Intravoxel incoherent motion MR imaging can simultaneously measure the diffusion and perfusion characteristics of brain tumors. Our aim was to determine the utility of intravoxel incoherent motion-derived perfusion and diffusion parameters for assessing the treatment response of metastatic brain tumor following gamma knife radiosurgery., Materials and Methods: Ninety-one consecutive patients with metastatic brain tumor treated with gamma knife radiosurgery were assessed by using intravoxel incoherent motion imaging. Two readers independently calculated the 90th percentile and the 10th percentile histogram cutoffs for perfusion, normalized CBV, diffusion, and ADC. Areas under the receiver operating characteristic curve and interreader agreement were assessed., Results: With the combination of the 90th percentile histogram cutoff for perfusion and the 10th percentile histogram cutoff for diffusion, the sensitivity and specificity for differentiating recurrent tumor and treatment were 79.5% and 92.3% for reader 1 and 84.6% and 94.2% for reader 2, respectively. With the combination of the 90th percentile histogram cutoff for normalized CBV and the 10th percentile histogram cutoff for ADC, the sensitivity and specificity for differentiating recurrent tumor and treatment were 69.2% and 100.0% for reader 1 and 74.3% and 100.0% for reader 2, respectively. Compared with the combination of 90th percentile histogram cutoff for normalized CBV and the 10th percentile histogram cutoff for ADC, adding intravoxel incoherent motion to 90th percentile histogram cutoff for normalized CBV substantially improved the diagnostic accuracy for differentiating recurrent tumor and treatment from 86.8% to 92.3% for reader 1 and from 89.0% to 93.4% for reader 2, respectively. The intraclass correlation coefficients between readers were higher for perfusion parameters (intraclass correlation coefficient range, 0.84-0.89) than for diffusion parameters (intraclass correlation coefficient range, 0.68-0.79)., Conclusions: Following gamma knife radiosurgery, intravoxel incoherent motion MR imaging can be used as a noninvasive imaging biomarker for differentiating recurrent tumor from treatment effect in patients with metastatic brain tumor., (© 2014 by American Journal of Neuroradiology.)

Background and Purpose: Intravoxel incoherent motion can simultaneously measure diffusion and perfusion characteristics. Our aim was to determine whether the perfusion and diffusion parameters derived from intravoxel incoherent motion could act as imaging biomarkers for distinguishing recurrent tumor from treatment effect in patients with glioblastoma., Materials and Methods: Fifty-one patients with pathologically confirmed recurrent tumor (n = 31) or treatment effect (n = 20) were assessed by means of intravoxel incoherent motion MR imaging. The histogram cutoffs of the 90th percentiles for perfusion and normalized CBV and the 10th percentiles for diffusion and ADC were calculated and correlated with the final pathology results. A leave-one-out cross-validation was used to evaluate the diagnostic performance of our classifiers., Results: The mean 90th percentile for perfusion was significantly higher in the recurrent tumor group (0.084 ± 0.020) than in the treatment effect group (0.040 ± 0.010) (P < .001). The 90th percentile for perfusion provided a smaller number of patients within an overlap zone in which misclassifications can occur, compared with the 90th percentile for normalized CBV. The mean 10th percentile for diffusion was significantly lower in the recurrent tumor group than in the treatment effect group (P = .006). Receiver operating characteristic curve analyses showed the 90th percentile for perfusion to be a significant predictor for differentiation, with a sensitivity of 87.1% and a specificity of 95.0%. There was a significant positive correlation between the 90th percentiles for perfusion and normalized CBV (r = 0.674; P < .001)., Conclusions: A histogram analysis of intravoxel incoherent motion parameters can be used as a noninvasive imaging biomarker for differentiating recurrent tumor from treatment effect in patients with glioblastoma.

Background and Purpose: It may be challenging to differentiate primary CNS lymphomas, especially primary CNS lymphomas with atypical MR features, from tumefactive demyelinating lesions by the use of conventional MR. This study aimed to investigate the usefulness of (1)H-MR spectroscopy for making this discrimination., Materials and Methods: Forty-four patients with primary CNS lymphomas and 21 with tumefactive demyelinating lesions were enrolled. Single-voxel (TE = 144 ms) (1)H-MR spectroscopy scans with the use of the point-resolved spectroscopy sequence were retrospectively analyzed. The Cho/Cr and Cho/NAA area ratios were calculated. The lipid and/or lactate peak was visually categorized into 5 grades on the basis of comparison with the height of the Cr peak. The (1)H-MR spectroscopy findings were compared in all of the primary CNS lymphomas and the tumefactive demyelinating lesions and in the subgroup of atypical primary CNS lymphomas and tumefactive demyelinating lesions. The thresholds and added value of (1)H-MR spectroscopy to conventional MR were calculated by use of receiver operating characteristic curves., Results: Discrepancies between all of the primary CNS lymphomas and tumefactive demyelinating lesions were found in the Cho/Cr ratio (P = .000), Cho/NAA ratio (P = .000), and the lipid and/or lactate peak grade (P = .000). Lymphoma rather than tumefactive demyelinating lesions was suggested when the Cho/Cr ratio was >2.58, the Cho/NAA ratio was >1.73, and a high lipid and/or lactate peak grade (grade >3) was seen. Higher Cho/Cr ratios, Cho/NAA ratios, and lipid and/or lactate peak grades were found in atypical primary CNS lymphomas when compared with those of tumefactive demyelinating lesions. The area under the receiver operating characteristic curve of conventional MR was improved from 0.827 to 0.870 when Cho/NAA ratio was added in the uncertain cases., Conclusions: (1)H-MR spectroscopy may be useful for differentiating primary CNS lymphomas from tumefactive demyelinating lesions. Cho/NAA ratio could provide added value to conventional MR imaging.

Background and Purpose: Recent clinical experience with EBV-positive PCNSL in patients without acquired immune deficiency syndrome showed that they tended to have atypical features seen on conventional MR imaging. The purpose of our study was to evaluate the MR imaging features of EBV-positive PCNSL in patients without AIDS and to compare these imaging findings with those of EBV-negative PCNSL., Materials and Methods: MR images were obtained in 55 consecutive patients with pathologically proved EBV-positive (n = 10) or EBV-negative (n = 45) PCNSL. We statistically analyzed the differences between the patient groups regarding the occurrence of tumor necrosis or hemorrhage and ADC, rCBVmax, rCBVr, and the Cho/NAA ratio in the tumor area., Results: Tumor necrosis and hemorrhage were observed in 9 (90%) and 7 (70%), respectively, of the patients with EBV-positive PCNSL; necrosis was observed in 8 (18%), and hemorrhage, in 3 (7%) patients with EBV-negative PCNSL (P < .0001 each). The necrotic core was hyperintense relative to contralateral white matter, as seen on DWI in 4 patients with EBV-positive PCNSL, though the ADC between the 2 patient groups did not differ significantly. rCBVmax, rCBVr, and the Cho/NAA ratios did not differ significantly between the 2 groups. The sensitivity and specificity of necrosis and hemorrhage for differentiating the 2 groups were 89.2% and 81.7% and 78.5% and 94.1%, respectively., Conclusions: Our initial clinical experience with a small number of patients suggests that EBV-positive PCNSL in patients without AIDS tends to present with atypical MR imaging features.

Background and Purpose: Detection of underlying tumor in patients with unknown-origin acute ICH may be difficult because acute hematoma may mask enhancement of tumor on postcontrast CT. We intended to investigate the clinical utility of DECT in differentiating tumor bleeding from pure ICH., Materials and Methods: Using a dual-source CT scanner, we obtained TNC single-energy and postcontrast DECT scans for 56 patients with unknown-origin spontaneous ICH. From the 2 sets of postcontrast DECT images obtained with different tube energy, EA (equivalent to conventional postcontrast CT), VNC, color-coded iodine overlay, fusion images of iodine overlay and VNC images were produced. The diagnostic performances of fusion, EA, and combined EA and TNC images for detecting underlying tumors were compared., Results: Of the 56 patients, 17 had primary or metastatic tumors (18 lesions) and 39 had nontumorous ICH. The sensitivities of fusion, EA, and combined EA and TNC images for detecting brain tumors were 94.4%, 61.1%, and 66.7%, respectively, and their specificities were 97.4%, 92.3%, and 89.7%, respectively. The areas under the ROC curves were 0.964, 0.786, and 0.842, respectively. Overall, the diagnostic performance of fusion images was significantly superior to EA (P = .006) and combined EA and TNC (P = .011) images., Conclusions: DECT may be useful in detecting underlying tumors in patients with unknown-origin ICH.

Background and Purpose: Current MRI with the CE T1-weighted sequence plays a limited role in the evaluation of facial neuritis due to prominent normal facial nerve enhancement. Our purpose was to retrospectively investigate the usefulness of the CE 3D-FLAIR sequence compared with the CE 3D-T1-FFE sequence in facial neuritis patients., Materials and Methods: We assessed 36 consecutive patients who underwent temporal bone MR imaging at 3T for idiopathic facial palsy. Two readers independently reviewed CE 3D-T1-FFE and CE 3D-FLAIR images to determine the degree of enhancement in each of 5 segments of the facial nerve. We compared AUCs using the Z-test, compared diagnostic performance of 2 MR techniques with the McNemar test, and evaluated interobserver agreement. The Pearson χ(2) test was used for each segment of the facial nerve., Results: The AUC of CE 3D-FLAIR (reader 1, 0.754; reader 2, 0.746) was greater than that of CE 3D-T1-FFE (reader 1, 0.624; reader 2, 0.640; P < .001). The diagnostic sensitivities, specificities, and accuracies were 97.2%, 86.1%, and 91.7%, respectively, for CE 3D-FLAIR, and 100%, 56.9%, and 78.5%, respectively, for CE 3D-T1-FFE. The specificity and accuracy of CE 3D-FLAIR were greater than those of CE 3D-T1-FFE (specificity, P = .029; accuracy, P = .008). The interobserver agreements for CE 3D-FLAIR (κ-value, 0.831) and CE 3D-T1-FFE (κ-value, 0.694) were excellent. Enhancement of the canalicular and anterior genu segments on CE 3D-FLAIR were significantly correlated with the occurrence of facial neuritis (P < .001 for canalicular; P = .032 and 0.020 for anterior genu by reader 1 and reader 2, respectively)., Conclusions: CE 3D-FLAIR can improve the specificity and overall accuracy of MR imaging in patients with idiopathic facial palsy.